/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.

You may alternatively use this source under the terms of a specific version of
the OGRE Unrestricted License provided you have obtained such a license from
Torus Knot Software Ltd.
-----------------------------------------------------------------------------
*/
#include "OgreStableHeaders.h"
#include "OgreLogManager.h"
#include "OgreHardwarePixelBuffer.h"
#include "OgreImage.h"
#include "OgreTexture.h"
#include "OgreException.h"
#include "OgreResourceManager.h"
#include "OgreTextureManager.h"

namespace Ogre {
	//--------------------------------------------------------------------------
    Texture::Texture(ResourceManager* creator, const String& name, 
        ResourceHandle handle, const String& group, bool isManual, 
        ManualResourceLoader* loader)
        : Resource(creator, name, handle, group, isManual, loader),
            // init defaults; can be overridden before load()
            mHeight(512),
            mWidth(512),
            mDepth(1),
			mNumRequestedMipmaps(0),
            mNumMipmaps(0),
			mMipmapsHardwareGenerated(false),
            mGamma(1.0f),
			mHwGamma(false),
			mFSAA(0),
            mTextureType(TEX_TYPE_2D),            
            mFormat(PF_UNKNOWN),
            mUsage(TU_DEFAULT),
            mSrcFormat(PF_UNKNOWN),
            mSrcWidth(0),
            mSrcHeight(0), 
            mSrcDepth(0),
            mDesiredFormat(PF_UNKNOWN),
            mDesiredIntegerBitDepth(0),
            mDesiredFloatBitDepth(0),
            mTreatLuminanceAsAlpha(false),
            mInternalResourcesCreated(false)
    {
        if (createParamDictionary("Texture"))
        {
            // Define the parameters that have to be present to load
            // from a generic source; actually there are none, since when
            // predeclaring, you use a texture file which includes all the
            // information required.
        }

		// Set some defaults for default load path
		if (TextureManager::getSingletonPtr())
		{
			TextureManager& tmgr = TextureManager::getSingleton();
			setNumMipmaps(tmgr.getDefaultNumMipmaps());
			setDesiredBitDepths(tmgr.getPreferredIntegerBitDepth(), tmgr.getPreferredFloatBitDepth());
		}

        
    }
	//--------------------------------------------------------------------------
	void Texture::loadRawData( DataStreamPtr& stream, 
		ushort uWidth, ushort uHeight, PixelFormat eFormat)
	{
		Image img;
		img.loadRawData(stream, uWidth, uHeight, eFormat);
		loadImage(img);
	}
	//--------------------------------------------------------------------------    
	void Texture::loadImage( const Image &img )
	{

        LoadingState old = mLoadingState.get();
        if (old!=LOADSTATE_UNLOADED && old!=LOADSTATE_PREPARED) return;

        if (!mLoadingState.cas(old,LOADSTATE_LOADING)) return;

		// Scope lock for actual loading
		try
		{
			OGRE_LOCK_AUTO_MUTEX
			std::vector<const Image*> imagePtrs;
			imagePtrs.push_back(&img);
			_loadImages( imagePtrs );

		}
		catch (...)
		{
			// Reset loading in-progress flag in case failed for some reason
			mLoadingState.set(old);
			// Re-throw
			throw;
		}

        mLoadingState.set(LOADSTATE_LOADED);

		// Notify manager
		if(mCreator)
			mCreator->_notifyResourceLoaded(this);

		// No deferred loading events since this method is not called in background


	}
    //--------------------------------------------------------------------------
    void Texture::setFormat(PixelFormat pf)
    {
        mFormat = pf;
        mDesiredFormat = pf;
        mSrcFormat = pf;
    }
    //--------------------------------------------------------------------------
    bool Texture::hasAlpha(void) const
    {
        return PixelUtil::hasAlpha(mFormat);
    }
    //--------------------------------------------------------------------------
    void Texture::setDesiredIntegerBitDepth(ushort bits)
    {
        mDesiredIntegerBitDepth = bits;
    }
    //--------------------------------------------------------------------------
    ushort Texture::getDesiredIntegerBitDepth(void) const
    {
        return mDesiredIntegerBitDepth;
    }
    //--------------------------------------------------------------------------
    void Texture::setDesiredFloatBitDepth(ushort bits)
    {
        mDesiredFloatBitDepth = bits;
    }
    //--------------------------------------------------------------------------
    ushort Texture::getDesiredFloatBitDepth(void) const
    {
        return mDesiredFloatBitDepth;
    }
    //--------------------------------------------------------------------------
    void Texture::setDesiredBitDepths(ushort integerBits, ushort floatBits)
    {
        mDesiredIntegerBitDepth = integerBits;
        mDesiredFloatBitDepth = floatBits;
    }
    //--------------------------------------------------------------------------
    void Texture::setTreatLuminanceAsAlpha(bool asAlpha)
    {
        mTreatLuminanceAsAlpha = asAlpha;
    }
    //--------------------------------------------------------------------------
    bool Texture::getTreatLuminanceAsAlpha(void) const
    {
        return mTreatLuminanceAsAlpha;
    }
    //--------------------------------------------------------------------------
	size_t Texture::calculateSize(void) const
	{
        return getNumFaces() * PixelUtil::getMemorySize(mWidth, mHeight, mDepth, mFormat);
	}
	//--------------------------------------------------------------------------
	size_t Texture::getNumFaces(void) const
	{
		return getTextureType() == TEX_TYPE_CUBE_MAP ? 6 : 1;
	}
	//--------------------------------------------------------------------------
    void Texture::_loadImages( const ConstImagePtrList& images )
    {
		if(images.size() < 1)
			OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, "Cannot load empty vector of images",
			 "Texture::loadImages");
        
		// Set desired texture size and properties from images[0]
		mSrcWidth = mWidth = images[0]->getWidth();
		mSrcHeight = mHeight = images[0]->getHeight();
		mSrcDepth = mDepth = images[0]->getDepth();

        // Get source image format and adjust if required
        mSrcFormat = images[0]->getFormat();
        if (mTreatLuminanceAsAlpha && mSrcFormat == PF_L8)
        {
            mSrcFormat = PF_A8;
        }

        if (mDesiredFormat != PF_UNKNOWN)
        {
            // If have desired format, use it
            mFormat = mDesiredFormat;
        }
        else
        {
            // Get the format according with desired bit depth
            mFormat = PixelUtil::getFormatForBitDepths(mSrcFormat, mDesiredIntegerBitDepth, mDesiredFloatBitDepth);
        }

		// The custom mipmaps in the image have priority over everything
        size_t imageMips = images[0]->getNumMipmaps();

		if(imageMips > 0) {
			mNumMipmaps = mNumRequestedMipmaps = images[0]->getNumMipmaps();
			// Disable flag for auto mip generation
			mUsage &= ~TU_AUTOMIPMAP;
		}
		
        // Create the texture
        createInternalResources();
		// Check if we're loading one image with multiple faces
		// or a vector of images representing the faces
		size_t faces;
		bool multiImage; // Load from multiple images?
		if(images.size() > 1)
		{
			faces = images.size();
			multiImage = true;
		}
		else
		{
			faces = images[0]->getNumFaces();
			multiImage = false;
		}
		
		// Check wether number of faces in images exceeds number of faces
		// in this texture. If so, clamp it.
		if(faces > getNumFaces())
			faces = getNumFaces();
		
        if (TextureManager::getSingleton().getVerbose()) {
            // Say what we're doing
            StringUtil::StrStreamType str;
            str << "Texture: " << mName << ": Loading " << faces << " faces"
                << "(" << PixelUtil::getFormatName(images[0]->getFormat()) << "," <<
                images[0]->getWidth() << "x" << images[0]->getHeight() << "x" << images[0]->getDepth() <<
                ") with ";
            if (!(mMipmapsHardwareGenerated && mNumMipmaps == 0))
                str << mNumMipmaps;
            if(mUsage & TU_AUTOMIPMAP)
            {
                if (mMipmapsHardwareGenerated)
                    str << " hardware";

                str << " generated mipmaps";
            }
            else
            {
                str << " custom mipmaps";
            }
            if(multiImage)
                str << " from multiple Images.";
            else
                str << " from Image.";
            // Scoped
            {
                // Print data about first destination surface
                HardwarePixelBufferSharedPtr buf = getBuffer(0, 0); 
                str << " Internal format is " << PixelUtil::getFormatName(buf->getFormat()) << 
                "," << buf->getWidth() << "x" << buf->getHeight() << "x" << buf->getDepth() << ".";
            }
            LogManager::getSingleton().logMessage( 
                    LML_NORMAL, str.str());
        }
		
		// Main loading loop
        // imageMips == 0 if the image has no custom mipmaps, otherwise contains the number of custom mips
        for(size_t mip = 0; mip<=imageMips; ++mip)
        {
            for(size_t i = 0; i < faces; ++i)
            {
                PixelBox src;
                if(multiImage)
                {
                    // Load from multiple images
                    src = images[i]->getPixelBox(0, mip);
                }
                else
                {
                    // Load from faces of images[0]
                    src = images[0]->getPixelBox(i, mip);
                }
    
                // Sets to treated format in case is difference
                src.format = mSrcFormat;

                if(mGamma != 1.0f) {
                    // Apply gamma correction
                    // Do not overwrite original image but do gamma correction in temporary buffer
                    MemoryDataStreamPtr buf; // for scoped deletion of conversion buffer
                    buf.bind(OGRE_NEW MemoryDataStream(
                        PixelUtil::getMemorySize(
                            src.getWidth(), src.getHeight(), src.getDepth(), src.format)));
                    
                    PixelBox corrected = PixelBox(src.getWidth(), src.getHeight(), src.getDepth(), src.format, buf->getPtr());
                    PixelUtil::bulkPixelConversion(src, corrected);
                    
                    Image::applyGamma(static_cast<uint8*>(corrected.data), mGamma, corrected.getConsecutiveSize(), 
                        static_cast<uchar>(PixelUtil::getNumElemBits(src.format)));
    
                    // Destination: entire texture. blitFromMemory does the scaling to
                    // a power of two for us when needed
                    getBuffer(i, mip)->blitFromMemory(corrected);
                }
                else 
                {
                    // Destination: entire texture. blitFromMemory does the scaling to
                    // a power of two for us when needed
                    getBuffer(i, mip)->blitFromMemory(src);
                }
                
            }
        }
        // Update size (the final size, not including temp space)
        mSize = getNumFaces() * PixelUtil::getMemorySize(mWidth, mHeight, mDepth, mFormat);

    }
	//-----------------------------------------------------------------------------
	void Texture::createInternalResources(void)
	{
		if (!mInternalResourcesCreated)
		{
			createInternalResourcesImpl();
			mInternalResourcesCreated = true;
		}
	}
	//-----------------------------------------------------------------------------
	void Texture::freeInternalResources(void)
	{
		if (mInternalResourcesCreated)
		{
			freeInternalResourcesImpl();
			mInternalResourcesCreated = false;
		}
	}
	//-----------------------------------------------------------------------------
	void Texture::unloadImpl(void)
	{
		freeInternalResources();
	}
    //-----------------------------------------------------------------------------   
    void Texture::copyToTexture( TexturePtr& target )
    {
        if(target->getNumFaces() != getNumFaces())
        {
            OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, 
                "Texture types must match",
                "Texture::copyToTexture");
        }
        size_t numMips = std::min(getNumMipmaps(), target->getNumMipmaps());
        if((mUsage & TU_AUTOMIPMAP) || (target->getUsage()&TU_AUTOMIPMAP))
            numMips = 0;
        for(unsigned int face=0; face<getNumFaces(); face++)
        {
            for(unsigned int mip=0; mip<=numMips; mip++)
            {
                target->getBuffer(face, mip)->blit(getBuffer(face, mip));
            }
        }
    }
	//---------------------------------------------------------------------
	String Texture::getSourceFileType() const
	{
		if (mName.empty())
			return StringUtil::BLANK;

		String::size_type pos = mName.find_last_of(".");
		if (pos != String::npos && pos < (mName.length() - 1))
		{
			String ext = mName.substr(pos+1);
			StringUtil::toLowerCase(ext);
			return ext;
		}
		else
		{
			// No extension
			DataStreamPtr dstream;
			try
			{
				dstream = ResourceGroupManager::getSingleton().openResource(
						mName, mGroup, true, 0);
			}
			catch (Exception&)
			{
			}
			if (dstream.isNull() && getTextureType() == TEX_TYPE_CUBE_MAP)
			{
				// try again with one of the faces (non-dds)
				try
				{
					dstream = ResourceGroupManager::getSingleton().openResource(
						mName + "_rt", mGroup, true, 0);
				}
				catch (Exception&)
				{
				}
			}

			if (!dstream.isNull())
			{
				return Image::getFileExtFromMagic(dstream);
			}
		}

		return StringUtil::BLANK;

	}


}
